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81.
82.
A combination of traditional taxonomic procedures and molecular techniques has provided new insight into the problems of cryptic species and sexual and ontogenetic polymorphism in the Tanaidacea. Using polymerase chain reaction and DNA markers, three cryptic species of Paratanais were identified. PCR primers were used to amplify the divergent internal transcribed spacers (ITS) of these species. Restriction digestion of the amplified rDNA generated species specific DNA banding. Male and five female stages of Paratanais maleticus sp. nov. and two other new species, P. malign us and P. perturbatius , are described. Morphological variation, both sexual and ontogenetic, was found in several generic characters of Paratanais and required the diagnosis to be modified. The identification of three undescribed cryptic species from a single microhabitat in a well studied, shallow water and easily accessible locality, demonstrate that the biodiversity of tanaid crustacean is significantly underestimated.  相似文献   
83.
麻叶千里光抗菌化学成分的研究(Ⅲ)   总被引:6,自引:0,他引:6  
以革兰氏阳性菌金黄色葡萄球菌(Staphylococcus aureus)、枯草芽孢杆菌(Bacillus subtilis)和阴性菌大肠杆菌(Escherichia coli)为受试菌,采用体外抑菌圈法追踪抗菌活性部分。利用各种色谱技术对正丁醇萃取部分进行分离纯化,根据理化性质和谱学数据进行结构鉴定。从麻叶千里光的水提醇沉物的正丁醇萃取部分分离得到3个化合物:苄基-O-α-L-广吡喃阿拉伯糖基(1→6)-β-D-吡喃葡糖苷(1)、(6S,9S)-6-羟基-3-酮-α-紫罗兰醇-9-O-β-D-葡糖苷(2)和(6S,9R)-6-羟基-3-酮-α-紫罗兰醇-9-O-β-D-葡糖苷(3)。它们均为首次从该属植物中分离得到。  相似文献   
84.
85.
This paper provides a review of the family Lucanidae in Korea, which consists of 17 species belonging to 9 genera. One new species, Dorcus tenuihirsutus sp. nov., is described and the following taxonomical changes are proposed: Aegus laevicollis Saunders, 1854 is newly identified as Aegus laevicollis subnitidus Waterhouse, 1873; Macrodorcas striatipennis Motschulsky, 1861 is removed from the Korean fauna because this record is thought to have been based on the misinterpretation of locality and misidentification; Neolucanus saundersii Parry, 1864 is removed from the Korean fauna because this record is thought to have been based on misidentification.  相似文献   
86.
Eleven polymorphic dinucleotide (GA and CA) microsatellites were isolated and characterized in the mosquito Anopheles sinensis; this species is distributed over the East Asia region and is a primary vector of malaria, particularly in Korea. The number of alleles per locus ranged from 4 to 13. The observed heterozygosity (HO) and expected heterozygosity (HE) varied from 0.30 to 0.89 and from 0.59 to 0.90, respectively. These microsatellites could be useful in studying the evolution of the widely distributed A. sinensis in diverse environments.  相似文献   
87.
The Plus ça change model predicts that deepwater trilobite species such as Triarthrus should exhibit gradual phyletic evolution. A detailed stratigraphic sequence of Triarthrus beckii specimens considered together with geographically separated samples from a single time interval provide a test of the Plus ça change model. We examined geographic patterns of variation in cranidial shape based on specimens from four approximately synchronous levels within the Upper Ordovician (lower Edenian) strata of New York, Québec, Kentucky and Pennsylvania. All geographic populations differ in mean size, except for New York and Pennsylvania. Because allometry is present in both meraspid and holaspid phases of the trilobite, size effects on shape were removed by ontogenetic standardization. Cranidial shapes were then compared among the four study sites and eight stratophenetic samples from New York, obtained by subdividing our Mohawkian Composite Standard Section into 20-m-thick intervals. Goodall's F-test of pairwise comparisons of cranidial shape between eight subintervals in New York and the other three populations are all significant. Geographic variation in cranidial size and shape in T . beckii appears to display a gradient or cline-like pattern that is related to paleogeography. Although cranidial shape is not entirely static within the New York stratophenetic series, it is in all cases different from that sampled elsewhere in the region. Thus, there is no evidence of wholesale immigration and emigration among the geographic areas. Instead, the geographic gradient of T . beckii shape variation may have remained fairly stable over ca. 3 million years during the mid-Chatfieldian to early Edenian interval. This result is indicative of stasis. Consequently, the evolutionary history of T . beckii contradicts the Plus ça change model.  相似文献   
88.
Toxicity of 4-nonylphenol (4-NP) in the Chironomidae Chironomus flaviplumus was analyzed using a proteomics approach that involved identifying proteins by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Proteome analysis of 4-NP-treated samples on silver stained gels found alterations in the expression levels of three proteins compared with control samples. Hsp70 proteins, so-called stress proteins, were studied in Chironomus flaviplumus exposed to different concentrations of 4-nonylphenol (0, 30, 100, 150, 300 and 600 mg/L) in the laboratory and in the field in captured animals from site 1 (1 km from a chemical factory) and site 3 (16 km from a chemical factory). Hsp70 proteins were found in all samples tested, including controls, but differed in their expression levels. At more polluted sites (site 1), the samples treated with higher concentrations of 4-NP more strongly expressed Hsp70. 2-D spots were induced or enhanced in gels following injection of 4-NP. Therefore, the induction of stress protein expression in Chironomus flaviplumus, in particular Hsp70, can be used as a biomarker for the evaluation of environmental conditions.  相似文献   
89.
90.
Chironomidae is usually the most abundant macroinvetebrate in freshwater. They form an important part of the foodweb, and also have long been known as indicators of water quality. However, there is a great deal of difficulty in its identification. Such is due to the complexity of larval taxonomy. The external fine structures of the mouth parts and antennae of 4th instar larva C. flaviplumus and C. salinarius were examined using scanning electron microscopy (SEM). The antennae of the fourth instar larvae of C. flaviplumus and C. salinarius are short and composed of five segments. They consist of a scape, pedical, and three flagellar subsegments. The maxilla palps have 10 sensilla basiconica on its distal surface. They show the three morphological groups in the following numbers: six apical sensillae, three medial sensillae, and one lateral sensillae. The mandibles have strong apical and lateral teeth. These sensory structures are situated on the head capsule, each of which are represented with images to elucidate the identification of chironomidae.  相似文献   
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